Tee-nuts are widely used in the furniture industry for securing components of furniture together. Various types of power-operated Tee-nut setting machines have been devised for the setting of Tee-nuts into a workpiece at a high rate of speed.
In one type of Tee-nut setting machine, Tee-nuts are fed from a hopper down a feed guide channel to a power-operated driving assembly for driving Tee-nuts into a workpiece. The endmost Tee-nut is releasably held in registration with the driving assembly by releasable finger means, or the like, biased by spring means.
However, this kind of finger means is not reliable and may sometimes fail to hold the Tee-nut in a desired position due to malfunction of the spring means.
Another type of Tee-nut setting machine is disclosed in U.S. Pat. No. 4,821,940 granted to Allan C. Rotherham on Apr. 18, 1989.
In order to control the feeding and positioning of Tee-nut in registration with a driver assembly, Rotherham's machine makes use of a step member between the endmost Tee-nut and the next Tee-nut in line. The endmost Tee-nut must be moved over the step member to a position where it is held in registration with the driving assembly. The remaining Tee-nuts in the feed guide channel are held back by the step member so that they do not interfere with the driving of the endmost Tee-nut.
In order to make the above arrangement work, a piston is employed to raise the endmost Tee-nut over the step member so that it can register with the driving assembly. The use of a piston to raise the endmost Tee-nut over a step member to a position in registration with a driving assembly is also not reliable as the piston may fail to work.
Furthermore, this mechanism is not suitable for Tee-nuts fed from a roll or drum wherein Tee-nuts are linked together by connecting means.